摘要
本文旨在研究内蒙古牧区冬春季低质粗料供给条件下,补饲不同能氮比精料对羔羊生长性能及血清指标的影响。采取单因子试验设计选取(61±2)日龄健康、体重为(20.56±1.43)kg断奶的羔羊128只,公母各占1/2,分成4组,每组32个重复,每个重复1只羊,分别补饲消化能(DE)水平相近、粗蛋白质(CP)水平逐渐升高的4种颗粒精料,其能氮比(采用DE/CP)分别为90.03(Ⅰ组)、82.55(Ⅱ组)、73.25(Ⅲ组)、67.87 M J/kg(Ⅳ组)。试验期40 d。结果表明:1)Ⅲ组平均日增重分别高于Ⅳ组7.75%(P<0.01)、Ⅰ组4.94%(P<0.05)和Ⅱ组3.41%(P>0.05),且该组料重比最优。2)Ⅰ组羔羊末体高极显著低于其他组(P<0.01),其中Ⅱ、Ⅲ、Ⅳ组母羔末体高分别比Ⅰ组高3.68%、4.12%、4.44%(P<0.05);不同能氮比精料对不同性别羔羊的胸围增长、胸围增长率无显著影响(P>0.05)。3)血清尿素氮含量随着精料蛋白质水平增加而升高,Ⅳ组极显著高于Ⅰ、Ⅱ组(P<0.01);Ⅲ组羔羊血清中白细胞介素-6含量显著高于Ⅱ、Ⅳ组(P<0.05),免疫球蛋白M含量显著高于其他各组(P<0.05)。结果提示,牧区冬春季枯草期对羔羊及时补饲精料能够取得较好的生长效果,不同能氮比精料对牧区羔羊部分血清指标产生显著影响,补饲精料最适能氮比为73.25 MJ/kg。
This study was aimed to investigate the effects of supplementation of concentrates with different ratios of energy to nitrogen on performance and serum indices in weaner lambs in pastoral areas of Inner Mongolia that only had low quality roughages in winter and spring. One hundred and twenty eight （ half male and half female） healthy weaner lambs aged （61±2） days with weight of （20.56±1.43） kg were assigned to four groups using single factor experimental design. There were 32 replicates in each group and 1 lamb in each replicate. Lambs in four groups were supplemented with concentrates with similar digestive energy （ DE） level and gradually increased crude protein （ CP） levels, and the ratio of energy to nitrogen （ calculated by DE/CP） was 90.03 （group Ⅰ）, 82.55 （group Ⅱ）, 73.25 （group Ⅲ） and 67.87 MJ/kg （group Ⅳ）, respectively. The experiment lasted for 40 days. The results showed as follows：1） average daily gain of groupⅢ was the high-est, and was 7.75%, 4.94%, 3.41% higher than that of groups Ⅳ （P〈0.01）, Ⅰ （P〈0.05） and Ⅱ （P〉0.05） , respectively. Moreover, group Ⅲ had optimal feed/gain. 2） Final withers height of groupⅠ was significantly lower than that of the other groups （P〈0.01）, that of female lambs of groups Ⅱ, Ⅲ and Ⅳ was 3.68%, 4.12% and 4.44% higher than that of group Ⅰ （P〈0.05）; the gain and growth rate of heart girth were not significantly affected by supplementation of concentrate with different ratios of energy to nitrogen or gender （ P〉0.05） . 3） Serum content of urinary nitrogen gradually increased with the increasing of concentrate protein level, and groupⅣ was significantly higher than groupsⅠ andⅡ （ P〈0.01）;serum content of inter-leukin 6 of group Ⅲ was significantly higher than that of groups Ⅱ and Ⅳ （ P〈0.05） , and serum content of immunoglobulin M was higher than that of the other groups （P〈0.05）. The results indicate lambs in pastoral areas can achieve better growth performance when they were timely supplied concentrate. Under conditions in the present study, concentrates with different ratios of energy to nitrogen have a significant impact on some serum indices, and the optimum ratio of energy to nitrogen of the concentrate is 73.25 MJ/kg.
出处
《动物营养学报》
CAS
CSCD
北大核心
2015年第1期289-297,共9页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
公益性行业(农业)科研专项(201303062)
关键词
牧区羔羊
补饲
能氮比
生长性能
血清指标
lambs in pastoral areas
supplementation
ratio of energy to nitrogen
growth performance
serum indices
